EP3580485B1

EP3580485B1 - Work hardened weld and method for producing such weld

Info

Publication number: EP3580485B1
Application number: EP18752029.1A
Authority: EP
Inventors: Yong Joo Kim; Stephen Douglas OBERMARK; Brent Michael SUMMERS; Austin Tyler HANES; William Francis OBERMARK
Original assignee: Webco Industries Inc
Current assignee: Webco Industries Inc
Priority date: 2017-02-13
Filing date: 2018-02-13
Publication date: 2024-03-27
Anticipated expiration: 2038-02-13
Also published as: ES2975314T3; US11014181B2; EP4425025A1; EP3580485C0; KR20190112139A; EP3580485A4; JP2020506064A; WO2018148718A1; BR112019016694A2; CA3052815A1; KR102089308B1; US20190381594A1; EP3580485A1; CA3052815C; CA3134247A1; US20210293359A1; MX2019009664A; JP6744500B2; BR112019016694B1; MX2021012167A

Description

TECHNICAL FIELD

This document pertains generally, but not by way of limitation, to metal components, such as pipes, tubes and the like and welded connections, and in particular to a tube assembly, an umbilical comprising such tube assembly and a method for coupling respective ends of first and second tubes as defined in claims 1, 15 and 16 respectively.

BACKGROUND

High strength tubes, pipes or the like (e.g., metal components) are used in a variety of applications because of their strength including yield strength, ultimate (tensile) strength, high fatigue life and the like. Further, in some applications tubes, pipes or the like are used in corrosive conditions including undersea or subterranean environments, mining, gas or oil production or the like. Metal components, such as stainless steel and nickel alloys are suited in some examples for use in these environments and also, when conditioned, provide a high strength component.
Metal components, in some examples, are welded to join components and enclose other components or form larger assemblies. In examples, welding uses a heat source to melt and join components. The component material is melted and then joined, for instance with a filler metal. One example of a welded assembly includes umbilicals used in offshore oil and gas production. The umbilical includes tubular segments that are connected by way of orbital welds and helically wound or bundled together with other components to form a wrapped and continuous unit that is encased in a jacket and extends to one or more pieces of equipment in the aquatic environment. The umbilical provides one or more of fluids, power, information (e.g., instructions, data streams or the like) to and from the pieces of equipment.
RU2 251 465 describes a method of assembling tubes, welding and bending them. Tubes are welded at forming seam whose length exceeds necessary value due to expansion of end portions of tubes
joined for assembling. Then tube is straightened by local plastic deformation of welded seam and near-seam zones by means of compression efforts while imparting to tube rotation and translation motion.

OVERVIEW

The present invention provides a tube assembly, an umbilical with such tube assembly and an associated method for coupling respective ends of first and second tubes as defined in the appended claims 1, 15 and 16 respectively.
Further preferred embodiments of the present invention are defined in appended claims.
The present inventors have recognized, among other things, that a problem to be solved includes minimizing the decrease in strength and corresponding weak point of welded components because of localized heating (annealing) of the base material (e.g., stainless steel, nickel based alloys or the like) proximate to welds. The metal components used in a variety of applications are, in some examples, conditioned (e.g., heat treated, cold worked and the like) to achieve specified mechanical characteristics including, but not limited to, one or more of yield strength, ultimate (tensile) strength, hardness and fatigue life. Further, these components are conditioned to provide high strength while at the same time maintaining ductility for formation of specified profiles and shapes when subjected to the appropriate tensile stress.
A conditioning technique for metal components includes work hardening (e.g., cold working or cold rolling). In work hardening the metal component such as a sheet or the like is plastically deformed and thereby increases the strength of the material (e.g., including one or more of yield strength, ultimate strength, hardness, fatigue life or the like).
Further, welding of components, including melting of the base material (such as stainless steel or nickel based alloys) anneals the base material proximate to the weld and creates a relatively weaker location in the assembly relative to the remainder of the base material. The weaker location contains both as-cast weld structure and a local heat affected zone (HAZ), a partially annealed form of the base material, both of which lack the strength of the base material (e.g., one or more yield or ultimate strength, hardness, fatigue life or the like). Because the weld and the HAZ extend through the components (e.g., from proximate an exterior surface to proximate an interior surface, or outside and inside diameters) work hardening of the weld assembly, for instance the weld fusion zone (e.g., including one or more of a weld filler, resolidified, weld-cast, as-cast, re-cast base material or the like), does not sufficiently modify the material structure of the HAZ consistently to increase the strength of the overall weld assembly proximate to the original strength of the base material. Accordingly, a weak location is formed that is prone to failure because of its lower strength relative to the base material of the components (e.g., tubes, pipes or the like).
The present subject matter helps provide a solution to this problem, such as by constructing and work hardening a weld assembly in a consistent and predictable manner that provides a higher strength connection between components. According to the present invention, the weld assembly includes mechanical characteristics including, but not limited to, one or more of yield strength, ultimate (tensile) strength, hardness, fatigue life or the like proximate (e.g., matching or within 55.16 MPa (8000 psi) or less of a specified yield strength) to the corresponding mechanical characteristics of the base material. In one example, the weld assemblies described herein provide a yield strength of 620.53 MPa (90,000 psi) or greater, for instance with a base material including a nickel alloy.
The detailed description is included to provide further information about the present patent application.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

Figure 1: is a schematic view of one example of an offshore oil or natural gas rig including an umbilical having a plurality of tube assemblies.
Figure 2: is a cross sectional view of the umbilical of Figure 1.
Figure 3: is a side view of one example of a tube assembly including a plurality of welded connections.
Figure 4A: is a detailed cross sectional view of a weld assembly for the tube assembly of Figure 3.
Figure 4B: is a detailed cross sectional view of another weld assembly for the tube assembly of Figure 3 having a work hardened configuration.
Figure 5A: is a detailed cross sectional view of an end profile of tubes having a J shape.
Figure 5B: is a detailed cross sectional view of another end profile of tubes having a V shape.
Figure 5C: is a detailed cross sectional view of another end profile of tubes having a U shape.
Figure 5D: is a detailed cross sectional view of another end profile of tubes having a square shape.
Figure 6: is a detailed cross sectional view of the tube assembly having the end profile shown in Figure 5A forming a tapered weld recess.
Figure 7A-1: is a detailed cross sectional view of the tube assembly of Figure 6 with a weld fusion zone within the tapered weld recess.
Figure 7A-2: is a detailed cross sectional view of the tube assembly of Figure 6 with a weld fusion zone within the tapered weld recess.
Figure 7B: is a detailed cross sectional view of the tube assembly of Figure 7A-2 with the weld fusion zone forming a weld skirt over portions of the component tubes proximate the shaped ends of the tubes.
Figure 8: is a detailed cross sectional view of the tube assembly of Figure 7B including a shaped weld skirt before work hardening.
Figure 9: is a detailed cross sectional view of the tube assembly of Figure 8 including a weld assembly in another example of a work hardened configuration.
Figures 10A-F: are cross sectional views of another example of a tube assembly in stages of forming a weld assembly.
Figure 11: is a block diagram showing a method for connecting at least first and second tubes.

DETAILED DESCRIPTION

Industries desire a high strength tube or pipe, tube product (e.g., tube assembly as provided herein) or the like. In some examples cold working (or work hardening) the product during production is used to increase the strength (e.g., yield strength of the product) of welded connections (e.g., weld assemblies). The techniques and examples provided herein provide strengthened weld assemblies having thoroughly work hardened weld fusion zones, weld interfaces (e.g., former heat affected zones created during welding). The weld assemblies according to the present invention have mechanical characteristics, such as yield strength or the like, proximate to a specified characteristic (such as yield strength) of the base material of the component tubes. In other configurations, the techniques and examples included herein provide controlled and predictable yield strengths while maintaining specified ductility (elongation) and uniformity (of strength). Further, the techniques provided herein also provide controlled and predictable hardness, ultimate strength (tensile strength) and related characteristics such as fatigue life (e.g., endurance limit).
The products and methods described herein include welded connections and associated localized zones of the base material that are consistently and predictably work hardened (e.g., cold worked, cold rolled or the like). Products (e.g., tubes, pipes or the like) including these improved strength welded connections have enhanced strength, including yield strengths (of at least 620.53 MPa (90,000 psi) in some examples) that facilitate the use of the products in extreme environments and conditions (e.g., offshore petroleum and natural gas production and mining, mining, drilling including down hole drilling, fluid transport and storage, work strings, velocity strings, capillary tubing, encapsulated wire tubing, casings, oil and gas production tubing, manufacturing, submersible vehicles, vehicles, space and atmospheric vehicles or the like). The methods of welding and work hardening welds described herein provide welded connections and local base materials interfacing with the welds having high strength. With the proprietary processes, significant and consistent strength recovery is achieved in products otherwise having limited strength welded connections.
The methods described herein are used with a variety of base materials including, but not limited to, materials that are cold worked (or work hardened) during production to achieve (e.g., increase) specified mechanical characteristics, such as yield strength, ultimate (tensile) strength, hardness and fatigue life. Materials include, but are not limited to, carbon steel, alloy steel, stainless steel, nickel based alloys, copper and copper alloys, beryllium and beryllium alloys, and titanium and titanium alloys. Stainless steels include duplex steels (e.g., S32205) and super duplex steels (e.g. S32750 or SAF2507^®, a registered trademark of Sandvik Intellectual Property AB Corporation; S32760; or Zeron ^® 100, a registered trademark of Weir Engineering Services Limited Co.). Example nickel based alloys include N06625; N08825; Hastelloy^®, a registered trademark of Haynes International, Inc.; Incoloy^®, and Inconel^® alloys, registered trademarks of Huntington Alloys Corporation.
Figure 1 shows a production system 100 for use in a subsea environment. As shown, the production system 100 includes a plurality of subsea production devices 104 coupled by way of umbilicals 106 to an installation vessel 102. In one example, the production system 100 includes the subsea production devices 104 in a distributed pattern, for instance, across a sea floor. As shown in Figure 1, a variety of subsea production devices 104 are spread away from vertically terminating umbilicals 106 and are accordingly spread from the vertically terminating umbilicals 106 by one or more horizontal umbilicals 106 resting along the sea floor.
In some configurations, subsea production devices 104 include, but are not limited to, umbilical termination assemblies, subsea distribution units, subsea control modules, production trees, electric flying leads, hydraulic flying leads or the like. As shown, the devices 104 are distributed away from the installation vessel 102. Each of the devices require one or more utilities including, but not limited to, fluids such as water, methanol, well fluids, compressed gases, electricity, hydraulic fluid as well as one or more of cabling, wiring or the like for monitoring and operation of the devices. In other configurations, the production devices 104 are configured to capture production fluids such as natural gas, oil or the like and deliver these fluids through the umbilicals 106 along flow lines to the installation vessel 102, for instance, for storage, transportation to other devices, vessels, rigs or the like.
Referring again to Figure 1, a plurality of umbilicals 106 are shown extending from the installation vessel 102 to the sea floor and across the sea floor to the one or more subsea production devices 104. Umbilicals 106 strung from the installation vessel 102 to the sea floor and across the sea floor have enhanced mechanical characteristics, for instance, one or more of ultimate (tensile) strength, hardness, fatigue life, yield strength or the like. For instance, in one configuration, umbilicals 106 extending from the installation vessels 102 and across the subsea floor are subjected to significant tensile stresses, compressive stresses or the like caused by the weight of the umbilicals 106 during deployment as well as suspension from the vessel 102, seawater pressure or the like. In one example, the umbilicals 106 are specified to have a yield strength of 620.53 MPa (90,000 psi) or more. Additionally, in other configurations, the umbilicals 106 are used in corrosive and high pressure environments requiring one or more additives, elements or the like to the material of the umbilicals 106 to facilitate the long term use of the umbilicals 106 in these environments. In one configurations, the umbilicals 106 include nickel, nickel alloys or the like configured to provide high strength and corrosion resistance within one or more environments including a subsea environment, a high temperature environment or combinations of the same.
Additionally, nickel alloys, when included with the umbilicals 106, are processed with one or more methods, for instance, by work hardening to increase the strength of the materials while at the same time maintaining the corrosion resistance provided by one or more of the alloying additives, such as, nickel. Work hardening includes one or more of cold working, cold rolling or the like that plastically deforms the base material of the umbilical 106, for instance, one or more of the sheaths, component tubes or the like comprising the umbilical. In one configuration, the cold working, cold rolling (e.g., work hardening) of the base material of the umbilical including one or more of the component tubes of the umbilical provides a high strength component or a portion of a high strength component configured to have a yield strength of at least 620.53 MPa (90,000 psi) or more. Work hardening of the base material of the component tubes provides enhanced mechanical characteristics to the component tubes while minimizing increases in wall thickness or the like that increase mechanical characteristics but adversely increase the weight of the umbilicals 106 (and accordingly introduce addition weight based stress).
Figure 2 shows an umbilical 106 in a cross-sectional view. As shown, the umbilical 106 includes a plurality of tubes such as a tube assembly 200. Each of the component tubes of the tube assembly 200 is configured to provide one or more utilities, for instance, to one or more of the subsea production devices 104 or facilitate the return of fluids, for instance, production fluids from the sea floor, for instance, along a flow line such as the central tube 200A shown in Figure 2. In another configuration, the tube assembly 200 includes one or more injection lines, such as the component tubes 200B, configured to provide one or more fluid based utilities such as water, chemicals, hydraulic fluid or the like to one or more of the production devices 104 provided on the sea floor. In another configuration, the component tubes 200B are configured to provide one or more chemicals, fluids such as water, or the like below the sea floor surface, for instance, to initiate production of one or more production fluids, such as natural gas, oil or the like. In another configuration, the tube assembly 200 of the umbilical 106includes one or more hydraulic control lines 200C (also component tubes) configured to provide varying flows of hydraulic fluid to and from one or more of the production devices 104 provided along the sea floor.
As shown in Figure 2, the umbilical 106 includes a plurality of one or more of the various tubes configured to provide a plurality of separate flows of the various utilities to one or more production devices. Accordingly, in some configurations, umbilicals 106 include a plurality of tubes in the tube assembly 200 and these component tubes may have diameters from around 3/8 inch to 12 inches or more. In still other configurations, the umbilicals 106 include one or more conduits, such as tubing or the like, configured to deliver one or more other utilities including, but not limited to, electrical power, monitoring and control, wiring, cabling (including structural support cabling) or the like between the installation vessel 102 (shown in Figure 1) and one or more production devices 104 provided along the sea floor. Optionally, additional component conduits (e.g., tubes) are included with the umbilical to provide structural support to the umbilical 106, such as enhanced tensile strength, during one or more of deployment to the sea floor or suspension from the installation vessel 102. Accordingly, the umbilicals 106 are, in some configurations, robust with a plurality of tubes included with the tube assembly 200. Additionally, in umbilicals 106 including one or more flow lines, such as the flow line 200A, the umbilicals are further enlarged to accommodate the flow of production fluids including, but not limited to, natural gas, crude oil or the like to the vessel 102, a rig or other storage or processing location, at the surface.
As further shown in Figure 2, the umbilical 106 is, in one configuration, constructed with one or more sheaths. In the configuration shown in Figure 2, the umbilical 106 includes an inner sheath 206 and an outer sheath 204. An armor jacket 208 is optionally provided between the inner and outer sheaths 206, 204. The inner and outer sheaths 206, 204 as well as the armor jacket 208 surround and protect the tube assembly 200 including the component tubes 200A, B, C previously described and shown herein. The armor jacket 208, in one configuration, includes steel, Kevlar (a registered trademark of E.I. Du Pont De Nemours and Company Corporation), or other structurally robust materials configured to protect the components within the umbilical 106, including sensitive components such as fiber optic cables, electrical cabling, wiring and to protect one or more of the fluid based utility line tubes 200B or the flow line tubes 200A from damage, for instance, from collisions with other umbilicals, friction or the like.
Additionally and in some configurations, the umbilical 106 includes an umbilical cavity 202 including, but not limited to, one or more interstitial spaces between various components of the umbilical, for instance, various component tubes of the tube assembly 200 (e.g., fluid flow lines, wiring and cable conduits, structural support tubes or the like) and various components (e.g., tubes, layers or the like) surrounding a tube such as a flow line 200A or the like. Tape, foam, adhesives or the like are provided, in one configuration, to lock the component tubes of the tube assembly 200 together. In still other configurations, the component tubes of the tube assembly 200 including, but not limited to, tubes 200A, 200B, 200C are wound helically to interlock the tubes with each other. The component tubes 200A, 200B, 200C are then positioned within one or more of the sheaths 206, 204, armor jacket 208 or the like to form the umbilical 106.
The materials used in the umbilical, including the tube assembly 200, include, but are not limited to, stainless steel, such as stainless steel 316L, duplex, super duplex, hyper duplex stainless steels, zinc coated nitronic 19D, nickel alloys or the like. The inclusion of one or more tubes, for instance, as shown in the tube assembly 200 as well as one or more of wiring, cabling, structural components such as steel cables, support tubes, carbon fiber rods, one or more sheaths 204, 206 and an armor jacket 208 (e.g., such as a Kevlar armor jacket) to the umbilical 106, in one configuration, increases the weight of the umbilical 106, for instance on a per unit length basis. Umbilicals 106 are suspended from an installation vessel 102 as shown in Figure 1 at least during installation, and in some configurations during production (as is the case with the vertically suspended umbilicals 106 shown in Figure 1). Umbilicals 106, in some configurations, extend thousands of feet to the sea floor, for instance, to the one or more subsea production devices 104 shown in Figure 1 and optionally extend across the sea floor to additional devices 104. Accordingly, the umbilicals 106 have enhanced mechanical characteristics to withstand the tensile forces incident on the umbilicals 106 when suspended from the installation vessel 102 as well as one or more of high pressure (compressive forces), high temperatures, corrosive environments or the like, for instance, along the sea floor.
To withstand these forces, pressure and environmental conditions the umbilical 106, for instance used and shown in Figure 1, includes one or more enhanced material characteristics including, for instance, a yield strength approaching 620.53 MPa (90,000 psi) or more. As previously described herein, and in at least some configurations, these materials (e.g., stainless steel, duplex, super duplex, hyper duplex stainless steels, nickel alloys and the like) are work hardened to enhance the strength of these materials and accordingly facilitate the suspension of the heavy umbilicals 106 from the installation vessel 102 thousands of feet, for instance, 4,000 feet, 5,000 feet, 6,000 feet, 7,000 feet, 8,000 feet or more. Accordingly, the umbilicals 106 described herein include sufficient structural integrity to remain suspended from the installation vessels 102 without fracturing, splitting, deforming or the like under their own weight when suspended.
Figure 3 shows one configuration of a component assembly 300, for instance, a tube assembly including a plurality of components such as a first component 302, a second component 304 and one or more supplemental components 306 (e.g., tubes). As shown, each of the components 302, 304, 306 are coupled in an end-to-end fashion, for instance, with one or more weld assemblies 310 provided therebetween. As further shown in Figure 3, each of the components includes respective component ends 308 provided proximate to each of the weld assemblies 310.
As further shown in Figure 3, the weld assemblies 310 provided between the first, second and supplemental components 302, 304, 306 interconnect each of the components and accordingly join the components to form the component assembly 300. An umbilical, such as the umbilical 106 shown in Figures 1 and 2, includes a plurality of components such as tubes 302, 304, 306 that are coupled in an end-to-end fashion, for instance, for each of the component tubes of the tube assembly 200. Stated another way, the plurality of tubes used in the tube assembly 200 as well as other components of the umbilical 106 are, in one configuration, end-to-end components such as the first, second and supplemental components 302, 304, 306 each joined together with weld assemblies 310 provided therebetween. With reference to Figure 1, the umbilicals 106 extending from the installation vessel 102 to the sea floor and across the sea floor to each of the one or more subsea production devices 104 includes, in some configurations, thousands of individual components such as interconnected first, second and supplemental components 302, 304, 306 in parallel and in series with each other. For instance, the components in parallel include one or more component tubes as shown in the cross-section of the umbilical 106, for instance in Figure 2. Each of the component tubes 200A, 200B, 200C of the tube assembly 200 in turn include multiple components, for instance, hundreds or thousands of component tubes welded from end to end, for instance, with interposing weld assemblies 310 shown in Figure 3.
Figure 4A shows a detailed cross-sectional view of a weld assembly 310A optionally used as the weld assembly 310 in Figure 3. In the configuration shown in Figure 4A, the weld assembly 310A includes a weld fusion zone 406 joining the first and second components 302, 304 at their respective component ends 308. As previously described, the components such as the first and second components 302, 304 are, in one configuration, constructed with the base material having enhanced mechanical characteristics including, but not limited to, ultimate or tensile strength, yield strength, hardness, fatigue life or the like.
Referring again to Figure 4A, the weld assembly 310A is shown with a weld fusion zone 406 positioned within a weld recess 408 between the component ends 308 of each of the first and second components 302, 304. The weld fusion zone 406 is applied to the first and second components 302, 304 between the tube exteriors 404 and the tube interiors 402 of each of the first and second component 302, 304, for instance with a thickness proximate to the side wall 400 thickness of the components. As shown, the weld fusion zone 406 includes one or more of a weld filler, resolidified base material or the like. The weld fusion zone 406 is also referred to as weld-cast, as-cast, re-cast or the like. The weld fusion zone 406 couples the first and second components 302, 304 together. Further, as shown in Figure 4A, a weld interface 410 is provided between the weld fusion zone 406 and the remainder of the base material of each of the components 302, 304. The high temperature of the weld fusion zone 406 (e.g., molten metal including one or more of a weld filler and melted base material) along the weld interfaces 410 anneals the (unmelted but adjacent) base material of the components 302, 304 proximate to the weld fusion zone 406. For instance, as shown in Figure 4A, the weld interface 410 is, , a heat affected zone. A heat affected zone (HAZ) has one or more decreased mechanical characteristics relative to the remainder of the base material of each of the components 302, 304. For instance, the yield strength, ultimate tensile strength or the like at the weld interfaces 410 have strengths 206.84 MPa (30,000 psi) or less relative to the base (work hardened and unannealed) material of the remainder of the components. Accordingly, the weld interfaces 410 provide a localized region of the component assembly 300 relatively weaker compared to the remainder of the base material used in the component assembly 300. Accordingly, when one or more of tension, compression or the like is applied along the component assembly 300, for instance while suspended from the installation vessel 102 shown in Figure 1, while positioned along the sea floor or the like, the component assembly 300 including the weld assembly 310A provides one or more weakened locations subject to failure.
Referring again to Figure 4A, the weld assembly 310A is work hardened, for instance, by one or more of cold working, cold rolling, hammering or the like to plastically deform the weld fusion zone 406 and a portion of the weld interface 410. Plastic deformation of the weld fusion zone 406 and the portion of the weld interface 410 enhances the strength in one or more of those components. For instance, a rolling mechanism, hammering mechanism or the like is applied along one or more of the faces of the components 302, 304, for instance, proximate to the weld assembly 310A to plastically deform the weld fusion zone 406 local to the applied force. The plastic deformation of the weld fusion zone 406, work hardens the weld fusion zone 406 and locally (relative to the applied force and plastic deformation) increases one or more of its mechanical characteristics such as ultimate strength, yield strength, fatigue life or the like relative to the base weld fusion zone 406.
Further, work hardening of the weld interface 410 (in contrast to the weld fusion zone 406), for instance, along one of the tube exterior 404, if work hardened from the exterior, or the tube interior 402, if work hardened from the interior, may incidentally enhance the mechanical characteristics of a portion of the weld interfaces 410. Because the weld interfaces 410 are substantially flush with the remainder of the base material of the components, such as the first and second components 302, 304, deformation of the weld interfaces 410 is proximate to either of the tube interior 402 or the tube exterior 404 (and may be absent) depending on where work hardening is performed and whether the weld interfaces are in fact plastically deformed at the weld assembly 310A. Accordingly, work hardening of the weld interfaces 410 is localized at the exterior 404 or interior 402 while the remainder of the weld interfaces 410 for instance, along at least a portion of weld interface segments 412 (shown in broken lines in Figure 4A) retains the heat affected or annealed configuration of the base material.
In this configuration, the weld interfaces 410 on either side of the weld fusion zone 406 (e.g., and corresponding the weld interface segments 412) are within the heat affected zone, remain annealed (and are not enhanced), and thereby have one or more decreased mechanical characteristics that remain depressed even after work hardening procedures. For instance, the weld interfaces 410 on each side of the weld assembly 310A have one or more of ultimate strength, yield strength or the like 206.84 MPa (30,000 psi) or less relative to the base material of the first and second components 302, 304. Accordingly, while the weld fusion zone 406 is, in this configuration, at least partially plastically deformed and includes mechanical characteristics that may approach the mechanical characteristics of the first and second components 302, 304 each of the weld interfaces 410, for instance the weld interface segments 412, extending from proximate the tube interior 402 to proximate the tube exterior 404 have mechanical characteristics less than the mechanical characteristics of these other components. Accordingly, the weld assembly 310A is prone to one or more of fracture, failure, fatigue based deformation or the like while the remainder of the component assembly 300 including, for instance, the base material of the first and second components 302, 304 (in a work hardened and unannealed configuration) maintains its relatively strong mechanical characteristics compared to the weld assembly 310A.
When the component assembly 300 including the weld assembly 310A is used in another assembly, such as the umbilical 106 shown in Figure 2, and then deployed or suspended (e.g., from an installation vessel 102) significant tensile stresses are applied to the umbilical 106. These tensile stresses, for instance 620.53 MPa (90,000 psi) or more, in some configurations may cause failure of the umbilical 106 at one or more of the weld assemblies 310A. Additionally, when used along a subsea surface (e.g., at extreme depths) the component assembly 300 including the weld assemblies 310A is subject to significant hydrostatic pressures (and corresponding stresses) and in other configurations may fail at the weld assemblies 310A. In some configurations, the side wall 400 is thickened to provide enhanced mechanical characteristics to offset weakness at the weld assemblies 310A. Thickening of the side wall 400 increases the mass of the component assembly 300 and accordingly generates additional tensile stresses that further aggravate failure at the weld assemblies 310A.
Figure 4B shows a cross-sectional view of another weld assembly 310B, for instance, used as the weld assembly 310 in Figure 3. In this configuration, the weld assembly 310B includes one or more portions of the components such as the first and second components 302, 304 (e.g., first and second tubes). The first and second components 302, 304 include component ends, such as tube ends, constructed with the base material of the remainder of the first and second components 302, 304 including, but not limited to, one or more of stainless steel, such as stainless steel 316L, duplex, super duplex, hyper duplex stainless steels, zinc coated nitronic 19D, nickel alloys or the like. As previously described, the first and second components 302, 304 are constructed with and then treated with one or more processes configured for use with stainless steel to provide enhanced mechanical characteristics. For instance, the first and second components are constructed with a base material such as nickel alloys, stainless steel, duplex stainless steel, super duplex stainless steel, hyper duplex stainless steel or the like. The base material is then work hardened by one or more of cold rolling or the like to impart enhanced mechanical characteristics including one or more of increased ultimate tensile strength, yield strength, fatigue life, hardness or the like relative to the unworked base material of each of the first and second components 302, 304.
As further shown in Figure 4B, the weld assembly 310B includes a weld fusion zone 420 positioned within a weld recess 424. In this configuration, the weld recess 424 extends from a recess root 426, for instance, proximate to the tube interior surface 402 and extends from the tube interior 402 surface across the sidewall 400 of each of the first and second components, 302, 304 to proximate the tube exterior surface 404. At the tube exterior the weld recess 424 opens or outwardly tapers to a recess opening 428 as shown in Figure 4B. In contrast to the weld assembly 310A shown in Figure 4A, the weld assembly 310B shown in Figure 4B tapers or laterally extends from the recess root 426 to the recess opening 428. Accordingly, the corresponding weld interfaces 422 of each of the first and second components 302, 304 are laterally extending, for instance from the recess root 426 proximate the tube interior surface 402 to proximate the tube exterior surface 404, for instance, corresponding to the recess opening 428. Accordingly, additional weld fusion zone 420 (optionally multiple passes of weld filler and molten base material) is provided within the weld recess 424 to fill the weld recess.
Additionally, as shown in broken lines in Figure 4B, prior to work hardening the weld fusion zone 420 is in this configuration layered above the tube exterior surface 404 of each of the first and second components 302, 304. For instance, the weld fusion zone 420 includes a weld skirt 423 extending to the left and right relative to the recess root 426.
As described herein, work hardening (e.g., cold rolling, cold working or the like) is applied to the weld assembly 310B including the weld fusion zone 420 to work harden the weld fusion zone 420 as well as the weld interfaces 422 sandwiched between the weld fusion zone 420 and the base material underlying the laterally extending weld interfaces 422. In this configuration, the underlying base material includes the portions of the sidewall 400 constructed with the base material that retain work hardened characteristics (e.g., are spaced from the weld fusion zone 420).
Referring again to Figure 4B, the weld fusion zone 420 as shown is provided within the weld recess 424, for instance, from the recess root 426 with a portion of the weld fusion zone including a base weld portion 421. In one configuration, the weld fusion zone 420 includes multiple passes to fill the weld recess 424 and provide a weld skirt 423 (e.g. of a weld filler mixed with resolidified base material or the like) extending over the lateral portions of the weld interfaces 422 of each of the first and second components 302, 304. Accordingly, as shown in Figure 4B, the weld fusion zone 420, when positioned within the weld recess 424 and applied as a weld skirt 423 extends over top of a portion of the first and second components 302, 304 and overlies the weld interfaces 422.
The weld fusion zone 420 is shown in Figure 4B in an upwardly tapering configuration, for instance, with the smallest portion of the taper proximate to the recess root 426 and proximate to the tube interior surface 402. In another configuration, the weld assembly 310B has a converse arrangement, for instance, with the recess root 426 positioned proximate to the tube exterior surface 404 and the recess opening 428 and the corresponding portion of the weld fusion zone 420 such as the weld skirt 423 positioned proximate to the tube interior surface 402.
The weld fusion zone 420 at application (e.g., application of a heated weld filler) includes one or more of weld filler, molten base material or the like. The weld fusion zone 420 heats (but does not melt) adjacent first and second components 302, 304 along the weld interfaces 422. Instead, the heated weld interfaces 422 are annealed and accordingly include heat affected zones (HAZ) therein. Annealing is most pronounced adjacent to the weld fusion zone 420 and gradually decreases across the weld interfaces 422 away from the zone 420 having the high temperature. The weld interfaces 422 (including HAZ prior to work hardening as described herein) accordingly have decreased mechanical characteristics including, but not limited to, yield strength, ultimate strength, hardness, fatigue life or the like relative to the base material of the remainder of the first and second components 302, 304 (e.g., outside of the weld interfaces 422). Accordingly, in this intermediate configuration (prior to the work hardened configuration shown in Figure 4B), the weld assembly 310B provides a localized weakness to the component assembly 300.
With work hardening of the weld assembly 310B having the configuration shown in Figure 4B the weld assembly 310B includes enhanced, consistent and predictable mechanical characteristics. Further, the enhanced mechanical characteristics are consistently and predictably provided along the weld fusion zone 420, and the weld interface segments 430 (shown in broken lines) extending from proximate the tube exterior surface 404 to proximate the tube interior surface 402. Stated another way, the mechanical characteristics of the weld assembly 310B are greater than the mechanical characteristics of the weld assembly 310A shown in Figure 4A. For instance, the weld assembly 310B constructed and work hardened in a manner described herein includes one or more of ultimate strength (including tensile strength), yield strength, hardness, fatigue life or the like approaching that of the base material of each of the first and second components 302, 304. For instance, each of the base material in the first and second components 302, 304 as well as the weld assembly 310B have yield strengths of 620.53 MPa (90,000 psi) or greater. In another example, the strength of the weld assembly 310B has one or more strengths including, for instance, yield strength, ultimate strength or the like within 55.16 MPa (8,000 psi), 41.37 MPa (6,000 psi), 27.58 MPa (4,000 psi), 13.79 MPa (2,000 psi) or the like of the (unannealed) base material of the first and second components 302, 304.
To achieve the mechanical characteristics specified with the weld assembly 310B, the weld fusion zone 420 shown in Figure 4B by the broken lines extends above one or more of the surfaces such as the tube exterior surface 404 or the tube interior surface 402 (in a converse configuration) of the components 302, 304. Additionally, a portion of the weld fusion zone 420, the weld skirt 423, extends laterally along a weld bed of the weld interfaces 422, for instance, from a bed root of the weld interfaces 422 proximate the recess root 426 to the bed opening proximate the recess opening 428.
Mechanical deformation of the weld fusion zone 420 projecting from the tube exterior surface 404, in this configuration, plastically deforms and drives the weld fusion zone 420 vertically into the first and second components 302, 304. As shown in Figure 4B, mechanical deformation (e.g., including work hardening, cold rolling, cold working or the like) drives the weld fusion zone 420 toward the weld interfaces 422 and the underlying component ends 308 of each of the first and second components 302, 304. Because the weld interfaces 422 are shaped as described herein the weld interfaces 422 extend laterally relative to the weld interfaces previously shown (in Figure 4A) the weld fusion zone 420 and the component ends 308 of each of the first and second components 302, 304 sandwich the weld interfaces therebetween. Additionally, HAZ follows the contour of the weld interfaces 422 and accordingly also extends laterally, and is not otherwise concealed or isolated in a column of HAZ (as in Figure 4A). Accordingly, work hardening of the weld fusion zone 420 plastically deforms the weld fusion zone 420 and correspondingly drives the zone 420 into the annealed weld interfaces 422. By driving the weld fusion zone 420 into the weld interfaces 422 extending laterally along the weld fusion zone 420, the weld interfaces 422 are plastically deformed and thereby work hardened in a similar manner to the weld fusion zone 420. The lateral extension (e.g., shape, profile or the like) of the weld interfaces 422 ensures HAZ in the weld interfaces 422 is exposed to plastic deformation from the weld fusion zone 420 and not otherwise isolated from deformation (e.g., as in the weld assembly 310A in Figure 4A).
In the configuration shown in Figure 4B, work hardening is present in at least the weld interface segments 430 (the broken line region) of the weld interfaces 422 extending from proximate to the tube exterior surface 404 to proximate to the tube interior surface 402. Work hardening is applied continuously through the weld assembly 310B, for instance, from proximate to the tube exterior surface 404 to proximate to the tube interior surface 402. The previously described annealed portions of the weld assembly 310A, for instance, corresponding to the weld interface segments 412 shown in Figure 4A are minimized (e.g., eliminated, decreased or the like). Instead, the weld assembly 310B includes work hardened weld interfaces 422 including weld interface segments 430 that are predictably and consistently plastically deformed to accordingly work harden the segments 430 and enhance mechanical characteristics of each of the weld fusion zone 420 and the weld interface segments 430 in comparison to the base materials of the first and second components 302, 304. Accordingly, the mechanical characteristics specified for the first and second components 302, 304 including one or more of ultimate strength such as tensile strength, yield strength, hardness, fatigue life and the like are carried through the weld assembly 310B.
Accordingly, the component assembly 300, including the weld assembly 310B, provides an assembly having consistent mechanical characteristics while minimizing localized weaknesses in the component assembly 300 that are otherwise subject to failure, for instance, an umbilical such as the umbilicals 106 shown in Figure 1 suspended from an installation vessel 102 to a sea floor and subject to tensile stresses. In contrast to the weld assembly 310A shown, for instance, in Figure 4A, having relatively large heat affected zones (HAZ) extending, for instance, from proximate the tube interior 402 to proximate the tube exterior 404, the weld assembly 310B, shown in Figure 4B, has consistently enhanced mechanical characteristics (relative to those of assembly 310A) between the tube exterior surface 404 and the tube interior surface 402 provided through plastic deformation transmitted through the weld fusion zone 420 to the weld interfaces 422 extending laterally as shown in Figure 4B. In some configurations, there is some variation in the mechanical characteristics between the exterior and interior surfaces 404, 402 because cold working is initiated proximate to the tube exterior surface 404. For instance, the yield strength of the weld assembly 310B proximate to the tube exterior surface 404 matches or even exceeds the yield strength of the base material, while the yield strength of the assembly 310B proximate the tube interior surface 402 (also enhanced by cold working) is optionally below that of the base material (e.g., 68.95 MPa (10,000 psi) or less). These variations are incidental compared to variations in the weld assembly 310A including example variations of 68.95 MPa (10,000 psi), 137.9 MPa (20,000 psi) or 206.84 MPa (30,000 psi) or more because the assembly 310A includes extensive heat affected zones (HAZ).
Further, in contrast to the extensive heat affected zones remaining in the weld assembly 310A shown in Figure 4A, the weld assembly 310B includes, in some configurations, incidental localized heat affected zones, for instance, proximate to the tube exterior surface 404 shown in Figure 4B by the heat affected beads 432. In another configuration, one or more heat affected zones remain in close proximity to the base of the weld assembly 3 10B, for instance, proximate to the recess root 426. In either of these configurations, the heat affected bead 432 provided proximate to the tube exterior surface 404, remaining portions of the weld interface 422 local to the recess root 426 or the like (including other incidental locations) are incidental components of the overall work hardened weld assembly 310B, and are in some configurations work hardened to various degrees through work hardening of the remainder of the assembly 310B. In still other configurations, and as described herein the degree of work hardening proximate the tube exterior surface 404 is greater than the work hardening proximate the tube interior surface 402 because work hardening is initiated along the tube exterior surface 404. Even with these variations, and as shown in Figure 4B, the work hardened weld interface segments 430 extending from proximate the tube interior surface 402 to proximate the tube exterior surface 404 provide overall consistently enhanced mechanical characteristics that ensure the weld assembly 310B has correspondingly enhanced mechanical characteristics approaching those of the base material when compared with the weld assembly 310A shown, for instance, in Figure 4A.
Figures 5A-D show configurations of component assemblies 501, 503, 505, 507 including a variety of end profiles for one or more of the component assemblies described herein. In describing each of these end profiles, the corresponding component assemblies 501, 503, 505 assist in shaping weld joints and the corresponding weld fusion zones (in the joints) to extend laterally. In at least some configurations, the laterally shaped joints and weld fusion zones enhance the work hardening of weld interfaces as well as the weld fusion zone to provide weld assemblies having mechanical characteristics approaching those of the base material of the components 302, 304 such as tubes or the like. These end profiles are formed with one or more methods including, but not limited to, machining, casting, rolling, die forming, forging or the like.
Referring first to Figure 5A, the component assembly 501 includes first and second components 302, 304 (e.g., a portion of first and second tubes is shown). The first and second components 302, 304 include the tube exterior surface 404 and tube interior surface 402. In Figure 5A, the end profiles 500 are provided in a J shape, for instance, having a laterally extending taper that opens toward the tube exterior surface 404 from proximate the tube interior surface 402. When the components ends 308 of each of the first and second components 302, 304 are positioned in close proximity to one another, a weld joint 502, for instance, a double J shape weld joint is formed by the end profiles 500.
Referring now to Figure 5B, a component assembly 503 is shown with the first and second components 302, 304 having the end profiles 504. In this configuration, the end profiles 504 have an angled taper, for instance, corresponding to a V shape. The end profiles 504 taper upwardly from proximate the tube interior surface 402 toward the tube exterior surface 404. With the first and second components 302, 304 positioned in close proximity to one another, for instance, with the respective component ends 308 provided in the adjoining fashion shown in Figure 5B, a weld joint 506 is formed. In this configuration, the weld joint 506 including end profiles 504 is a V shape weld joint.
Figure 5C shows another configuration of a component assembly 505 having a U shape weld joint 510. As with the previous configurations, the component assembly 505 includes first and second components 302, 304 such as tubes or the like. Each of the components includes component ends 308. In Figure 5C, the component ends include end profiles 508, for instance, having a U shape. The end profiles 508 as shown in Figure 5C extend in a lateral (though attenuated) fashion similar to the profiles shown in Figures 5A, 5B. Accordingly, a weld fusion zone and resulting weld interface including heat affected zones (HAZ) extends in a corresponding lateral fashion similar to the weld interfaces 422 shown in Figure 4B.
Figure 5D shows a differing configuration of a component assembly 507 providing a butt type weld joint 514 between the first and second components 302, 304. As shown in Figure 5D, the end profiles 512 are flat or have a square shape and accordingly facilitate the butt joining of the first and second components 302, 304 at their component ends 308. The weld joint 514 allows for the application of a bead of weld filler therebetween and, in some configurations, facilitates the application of multiple passes of the weld filler between the end profiles 512. The weld filler heats and melts the adjacent base material to form a weld fusion zone. Optionally, the weld joint 514 is used in an autogenous weld including weld-cast of the base material (e.g., melted and resolidified base material to form the weld fusion zone). In contrast to previous configurations described herein, the weld joint 514 extends in a steep or generally vertical fashion relative to the laterally extending weld joints previously shown, for instance, in Figures 5A, 5Band 4B. As will be described herein, the weld joint 514 including, for instance, a butt weld joint as well as the other component assemblies shown in Figures 5A, 5B, 5C, 4B are in one configuration, work hardened with a work hardening mechanism, method or the like described herein including profile work hardening of the weld assembly as well as the end profiles, such as the weld interface 512 of each of the first and second components 302, 304 shown in Figure 5D. As will be described, by deforming the entirety of the component assembly including, for instance, the component ends 308, the end profiles 512 and the weld fusion zone between the end profiles 512 work hardening is provided in a consistent fashion, for instance, from proximate the tube interior surface 402 to proximate the tube exterior surface 404.
In another configuration, the end profiles 512 of the weld joint 514 are melted, for instance, during tungsten inert gas (TIG) welding, to form a tapered, laterally extending weld fusion zone similar to the weld fusion zone shown 420 in Figure 4B. For instance, the base material adjacent the weld joint 514 and proximate the tube exterior surface 404 is melted preferentially (to a larger degree) than the base material proximate the tube interior surface 402. The weld assembly that began with the butt weld joint 514 accordingly assumes a tapered configuration having a weld fusion zone that extends laterally in a manner consistent with at least the weld fusion zone 420. Stated another way, the creation of the weld fusion zone between the end profiles 512 is used to shape weld interfaces into a laterally extending profile (and corresponding stack or sandwich of the fusion zone, interfaces and the base material). Accordingly, even a butt weld joint 514 as shown in Figure 5D is configured for work hardening as described herein, including for instance driving of the weld fusion zone into the laterally extending weld interface stacked between the base material and the fusion zone).
In still another configuration, the end profiles 512 of the weld joint 514 are optionally covered with a weld skirt, as previously described herein. Because the weld interfaces (e.g., end profiles 512) are steep or generally vertical, additional material is included in the weld skirt, for instance, the weld skirt includes one or more of additional lateral coverage (outwardly from the weld recess) or additional height relative to the tube exterior surface 402. Either or both of these changes to the weld skirt provide a more pronounced weld skirt than that shown in other figures herein. The pronounced weld skirt includes additional material for plastic deformation during work hardening. Work hardening of this weld skirt (e.g., into the weld joint 514 and the adjacent weld interfaces) causes extensive plastic deformation in the weld fusion zone and along the weld interfaces, and accordingly consistently and predictably work hardens steep or generally vertical weld assemblies (in addition to the laterally extending weld joints and interfaces of other weld assemblies described herein).
Figure 6 shows a detailed view of the cross-sectional component assembly 501 previously shown in Figure 5A. In this configuration, the component assembly 501 (e.g., a tube assembly) includes the first and second components 302, 304 tubes in close proximity to one another. As previously described, the end profiles 500 of each of the component ends 308 of the first and second components 302, 304 provides a double J shape weld joint 502. The weld recess 602 of the component assembly 501 follows the contour of the end profiles 500 and accordingly extends in a lateral fashion, for instance, from the recess root 604 to the recess opening 606. As shown in Figure 6, the recess root 604 is in proximity to the tube interior surface 402 while the recess opening 606 is in proximity to the tube exterior surface 404 (and remote from the tube interior surface 402). In another configuration, and as previously described herein, one or more of the end profiles such as the end profile 500 or one of the other end profiles shown, for instance, in Figures 5B, 5C or the like, are provided along the tube interior surface 402. In this inverse configuration, the recess root 604 is positioned in proximity to the tube exterior surface 404 while the recess opening 606 is provided in proximity to the tube interior surface 402.
As further shown in Figure 6, the end profiles 500 form the tapered profile of the weld joint 502 and the weld interfaces 608. The end profiles 500 (and the weld interfaces 608) optionally extend along the recess root 604 proximate to the tube interior surface 402. In this configuration (an intermediate configuration of the component assembly 501 prior to welding and work hardening), the weld interfaces 608 have mechanical characteristics corresponding to those of the base material of the components 302, 304. For instance where the first and second components 302, 304 include one or more of work hardened stainless steel, duplex stainless steel, super duplex stainless steel, hyper duplex stainless steel, zinc coated nitronic 19D, nickel alloys or the like, the weld interfaces 608, in this configuration (prior to welding) also have those matching (e.g., identical or substantially similar) characteristics. For instance, the weld interfaces 608 prior to joining at the weld fusion zone include work hardened (unannealed) structure and thereby have similar or identical characteristics to the remainder of the first and second components. These characteristics include, but are not limited to, one or more of yield strength, ultimate strength, hardness, fatigue life or the like.
The component assembly 501 including the end profiles 500 shown in Figure 6 is the base profile used in the component assembly in each of Figures 7A-9 as shown herein. The component assembly 501 is accordingly shown in an intermediate configuration in Figure 6 and processed as shown in each of the proceeding figures.
Figure 7A-1 shows a first intermediate configuration of the component assembly 501. In this intermediate configuration, a weld fusion zone 702 is provided within the weld recess 602, for instance, within the recess root 604 of the recess 602. The weld fusion zone 702 optionally includes an autogenous zone at the recess root 604 or fusion zone including weld filler mixed with molten base material. As shown, the weld fusion zone 702, in this configuration, is provided as a first pass within the recess root 604 and partially fills the weld recess 602. The remainder of the recess such as the recess opening 606, in this intermediate configuration, remains open. As further shown in Figure 7A-1, the weld interfaces 608 on each side of the component assembly 501 extend from the recess root 604 laterally toward the tube exterior surface 404. Accordingly, in this configuration, the component assembly 501 including the weld interfaces 608 extends from proximate the recess root 604 (e.g., also proximate to the tube interior surface 402) to proximate the tube exterior surface 404. In the configuration shown in Figure 7A-1, the weld fusion zone 702 extending along the weld interfaces 608 heats the base material of the first and second components 302, 304 and accordingly transitions the base material to a heat affected zone 700. The HAZ 700 extends along the weld interfaces 608 adjacent to the weld fusion zone 702.
As shown in Figure 7A-2, the weld fusion zone 702 fills the weld recess 602, for instance, to the recess opening 606. In the view shown, the weld fusion zone 702 extends from the recess root 604 proximate to the tube interior surface 402 to proximate the tube exterior surface 404 (e.g., the recess opening 606). Accordingly, in this configuration the weld recess 602 is filled by one or more passes of the weld fusion zone 702 (e.g., including one or more of weld filler, weld-cast or molten base material or the like). For instance, a supplemental weld portion 706 is provided over the base weld portion 704. The supplemental weld portion 706 includes, but is not limited to, one or more additional passes with the weld fusion zone 702 within the weld recess 602.
As further shown in Figure 7A-2, the heat affected zone (HAZ) 700 of the base material extends along the weld fusion zone 702 and the weld interface 608. With the weld fusion zone 702 applied within the weld recess 602, the base material at the weld interfaces 608 is annealed (forming HAZ 700) and accordingly the mechanical characteristics of the base material are depressed along the weld interfaces 608. For instance, as previously described herein, one or more of ultimate strength, yield strength, hardness, fatigue life or the like are decreased in the component assembly 501. As previously described herein, the HAZ 700 and the weld interfaces 608 extend laterally, and follow the contour of the weld recess 602 as provided by the end profiles 500 of each of the first and second components 302, 304. The weld fusion zone 702 extends in a complementary and lateral manner, for instance, from the recess root 604 to the recess opening 606. Further, as shown in Figure 7A-2, the laterally extending weld interfaces 608 and corresponding HAZ 700 are between the weld fusion zone 702 (above) and the unannealed base material of the first and second components 302, 304 (below). For instance, the weld interfaces 608 and HAZ 700 are sandwiched or stacked therebetween.
Optionally, even steep or vertical profiles, such as the end profiles 512 for a butt weld joint 514 (see Figure 5D) are conditioned to form laterally extending weld interfaces 608 and corresponding laterally extending HAZ 700 (within or part of the interfaces). As previously described herein, the end profiles 512 of the weld joint 514 are melted, for instance, during tungsten inert gas (TIG) welding, to form a tapered weld profile similar to the profiles shown in Figures 5A, 5B. For instance, the base material adjacent the weld joint 514 and proximate the tube exterior surface 404 is melted preferentially (to a larger degree) than the base material proximate the tube interior surface 402. Preferential melting of the base material transitions the butt weld joint 514 to a tapered configuration having a weld fusion zone (including weld-cast base material) that extends laterally in a manner consistent with the weld fusion zone 420 shown in Figure 4B (and other configuration lateral extending fusion zones provided herein). The remaining solid, but annealed, base material of the weld interfaces has a corresponding lateral contour to the weld fusion zone. Stated another way, the creation of the weld fusion zone between the end profiles 512 shapes weld interfaces in a laterally extending profile. Accordingly, even a butt weld joint 514 as shown in Figure 5D in some configurations is configured for work hardening as described herein (e.g., driving of the weld fusion zone into the laterally extending weld interface having a heat affected zone).
Referring now to Figure 7B, the component assembly 501 is in another intermediate configuration with an additional portion of the weld fusion zone 702 provided. As shown in Figure 7B, the additional portion of the weld fusion zone 702 includes a weld skirt 708 over top of the supplemental weld portion 706 and base weld portion 704. In another configuration, the weld fusion zone 702 is applied in a single step, for instance, with a larger volume of weld filler and molten base material applied to the entirety of the weld recess 602 (e.g., in a single pass) and optionally includes the weld skirt 708.
As shown in Figure 7B, the weld fusion zone 702 including the weld skirt 708 extends laterally relative to the base weld portion 704 and the supplemental weld portion 706. The weld skirt 708, in one configuration, follows the contour provided by the weld interfaces 608 formed as previously described herein, for instance, with one or more of a J profile, U profile, V profile or the like. In the configuration shown in Figure 7B, the weld skirt 708 projects from one or more surfaces of the component assembly 501. In this configuration, the weld skirt 708 projects vertically relative to the tube exterior surface 404. In another configuration, the weld fusion zone 702 projects from the tube interior surface 402, for instance, where the component assembly 501 is reversed with the profile of the weld interfaces 608 extending in a converse manner and taper from the recess root 604 proximate the tube exterior surface 404 toward the recess opening 606 proximate the tube interior surface 402.
Figure 7A-2 and Figure 8 show a weld assembly 710 in a complete or near complete configuration prior to work hardening. Because the weld assembly 710 is not work hardened the heat affected zones (HAZ) 700 are provided along the weld fusion zone 702 and within the weld interfaces 608 of the weld assembly 710. Although the weld assembly 710 in the intermediate configuration shown in Figure 7A-2 does not include the weld skirt shown in Figure 8, the weld assembly 710 is, in one configuration, configured for work hardening as described herein (e.g., to provide one or more material characteristics consistent with the base material of the components 302, 304). For instance, in one configuration, the weld assembly 710 in Figure 7A-2 is plastically deformed by driving the weld fusion zone 702 into the weld interfaces 608 and the HAZ 700 therein. The weld fusion zone 702 is mechanically deformed to an elevation less than the tube exterior surface 404. For instance, the weld fusion zone 702 is mechanically deformed (e.g., depressed) toward the tube interior surface 402 and the weld interfaces 608. In this configuration, the plastic deformation of the weld fusion zone 702 drives the weld fusion zone 702 into the HAZ 700, and the weld interfaces 608 including the HAZ 700 are plastically deformed and thereby work hardened.
In contrast to the weld assembly shown in Figure 7A-2, the weld assembly 710 shown in Figure 7B includes the weld fusion zone 702 projecting away from the tube exterior surface 404 with a weld skirt 708. In one configuration, the weld fusion zone 702 in this configuration is mechanically deformed to drive the weld fusion zone 702 into the component assembly 501 and thereby also mechanically deform the underlying weld interfaces 608 including the HAZ 700 therein. As previously described, the deformation of the weld fusion zone 702 deforms the HAZ 700 and work hardens the weld interfaces 608 thereby increasing the mechanical characteristics of the weld assembly 710. In one configuration, the mechanical characteristics of the weld assembly 710 are increased and, approach or equal the mechanical characteristics of the base material of the components 302, 304 including work hardened base materials of the components. In other configurations, the weld fusion zone 702 including, for instance, the weld skirt 708 as shown in Figure 7B is deformed into a flush configuration with the tube exterior surface 404. In another configuration, the weld fusion zone 702 is deformed relative to the intermediate configuration shown in Figure 7B, for instance, to an elevation between the elevation shown for the weld fusion zone 702 and the tube exterior surface 404 (e.g., projecting from the tube exterior surface 404 to a lesser degree relative to the weld fusion zone 702 as originally shown in Figure 7B). In still other configurations, the weld fusion zone 702 is deformed into a depressed configuration relative to the tube exterior surface 404 (as described with regard to Figure 7A-2 above). In this configuration, the weld fusion zone 702 including the weld skirt 708 has a recessed or depressed configuration, for instance, below the tube exterior surface 404.
Figure 8 shows another example intermediate configuration of the component assembly 501 including the weld assembly 710. In this configuration, the component assembly 501 includes a shaped weld skirt 800. For instance, the weld fusion zone 702 such as the projecting portion of the weld skirt 708 shown in Figure 7B is processed (e.g., by machining or the like) to provide the weld fusion zone 702 at a consistent elevation relative to the tube exterior surface 404. In some configurations, the weld skirt 708 is shaped to a specified height, for instance, the height shown in Figure 8. Work hardening of the weld fusion zone 702 including the shaped weld skirt 800 from the elevation or specified height shown in Figure 8 to a flushed configuration or other height relative to the tube exterior surface 404 (e.g., including above or below the tube exterior surface) is configured to increase the mechanical characteristics of the weld assembly 710 including the weld fusion zone 702 and the weld interfaces 608 to characteristic values that are proximate to, equal to, greater than or approaching the mechanical characteristics of the base material, for instance, of work hardened components 302, 304.
In one configuration, the specified height of the shaped weld skirt 800 corresponds to a height dimension previously determined, for instance, by way of lookup tables, empirical testing or the like that when plastically deformed (e.g., to a flush configuration as in Figure 9) increases the mechanical characteristics of the weld assembly 710 to values proximate those of the base material. That is to say deformation of the weld fusion zone 702 from the elevated position shown with a shaped weld skirt 800 to a flush configuration achieves one or more mechanical characteristics with the weld assembly 710 approaching or proximate to those of the base material. By plastically deforming the weld fusion zone 702 having the specified height the mechanical characteristics of the weld assembly 710 are consistent in the weld assembly because the deformation (in this case a decrease in elevation) is consistent.
Figure 9 shows one configuration of a completed work hardened weld assembly 900. In this configuration, the weld fusion zone 702 is work hardened relative to the configuration previously shown in Figure 8. For instance, the weld fusion zone 702 having the shaped weld skirt 800 is plastically deformed and driven into the component assembly 501. In this configuration, the weld fusion zone 702 is flush with the tube exterior surface 404. As shown in Figure 9, forces applied to the component assembly 501, for instance, at the weld assembly 900 are shown with solid arrows. In this configuration, mechanical deformation is initiated along the tube exterior surface 404, for instance, in a localized manner relative to the weld assembly 900. In other configurations, deformation is also provided in an opposed direction, for instance, from the interior of the component assembly 501 along the tube interior surface 404. In this configuration (shown with the dashed arrows), one or more of support, additional force (including force provided by interior based work hardening tools) or the like is applied along the tube interior surface 404 to accordingly support the component assembly 501 and provide a base to the component assembly 501 during plastic deformation of the weld fusion zone 702, weld interfaces 608 and the like. In an configuration having one or more of support or additional forces (including opposed work hardening) provided along the tube interior surface 404, the work hardening depression 904 or inward deformation shown in Figure 9 is absent. Instead, the tube interior surface 404 has a substantially isodiametric configuration extending from left to right in Figure 9.
In the configuration shown in Figure 9, the weld fusion zone 702, weld interfaces 608 and the like are plastically deformed with force applied along the tube exterior surface 404. As previously described, the first and second components 302, 304 underlying the weld fusion zone 702 and the weld interfaces 608 (e.g., in a stack, sandwich or the like) are constructed with base materials having enhanced mechanical characteristics including one or more of ultimate strength, yield strength, hardness, fatigue life or the like. These robust materials provide the base or support for the weld fusion zones 702 and the weld interfaces 608 during plastic deformation caused, for instance, by forces applied along the tube exterior surface 404. In this configuration, the work hardening depression 904 shown in Figure 9, is optionally included with the component assembly 501.
The weld fusion zone 702 shown in Figure 9 is provided in a graduated configuration and extends laterally, for instance, from the recess root 604 to one or more edges of the recess opening 606 within the weld recess 602. As previously described, the weld recess 602 is bounded by the end profiles of the components 302, 304 (e.g., one or more of the profiles described herein or the like) and recess and weld interfaces 608 extend laterally. Accordingly, the HAZ 700 (shown in Figure 8 prior to work hardening) also extends laterally relative to the weld fusion zone 702 and the weld recess 602. In this laterally extending configuration the weld interfaces 608 are a weld bed for the weld fusion zone 702. The weld interfaces 608 (e.g., weld bed) include one or more of weld bed floors 802, for instance, extending laterally and over the unannealed base material of the components 302, 304, and weld bed ceilings 804 extending laterally and under the weld fusion zone 702. In this configuration shown originally in Figure 8 and shown again in Figure 9, the weld fusion zone 702, the weld interfaces 608 and the base material of the underlying first and second components 302, 304 form a stacked configuration and accordingly sandwich the weld interface 608 as well as the HAZ 700 (shown in Figure 8) therebetween. As force is applied (as shown in Figure 9) transverse to the stacked layers of the weld fusion zone 702, weld interfaces 608 and the underlying base material of the components 302, 304 the weld fusion zone 702 is driven into the sandwiched weld interfaces 608. The plastic deformation transmitted through the weld fusion zone 702 and continued into the weld interfaces 608 work hardens both the weld fusion zone 702 and the laterally extending weld interfaces 608 including the HAZ 700 therein. Because the weld interfaces 608 extend laterally (e.g., from proximate the recess root 604 to proximate the recess opening 606) deformation of the weld fusion zone 702 is reliably transmitted to the weld interfaces 608 to plastically deform the HAZ 700 (shown in Figure 8) in a distributed manner in contrast to a local manner with vertical or steep angled weld interfaces 410 (e.g., proximate the surfaces 402, 404 as shown in Figure 4A). The weld interfaces 608 of the work hardened weld assembly 900, for instance interface segments extending from proximate the recess root 604 to proximate the recess opening 606, are consistently and predictably work hardened. In accordance with the present invention, the work hardened weld assembly 900 shown in Figure 9 including, but not limited to, the weld fusion zone 702, the weld interfaces 608, as well as the surrounding base material of the components 302, 304 underlying and adjacent to the weld interfaces 608 includes a work hardened mechanical characteristic (e.g., yield strength, ultimate strength, fatigue life or the like) proximate that of the base material (e.g., within one or more of 6.89 MPA (1,000 psi) or less, 13.79 MPa (2,000 psi) or less, 27.58 MPa (4,000 psi) or less, 41.37 MPa (6,000 psi) or less, 55.16 MPa (8,000 psi) or less of the base material). Then the work hardened weld assembly 900 has enhanced mechanical characteristics proximate to the base material as opposed to significant variation between other weld assemblies and the base material (e.g., as in the configuration shown in Figure 4A), for instance, variations of around 206.84 MPa (30,000 psi) in one or more mechanical characteristics, such as yield strength or the like.
In a configuration, the work hardened weld assembly 900 further includes one or more heat affected beads 902, for instance, provided at the edge of the weld assembly 900. These heat affected beads 902 are provided in the weld interfaces 608 and beyond the edges of the weld fusion zone 702. Because the weld fusion zone 702 heats and thereby anneals adjacent base material of the first and second components 302, 304, the heat affected beads 902 constitute a minimal portion (e.g., incidental portion) of the base material that remains heat affected or annealed at the edges of the weld assembly 900 after work hardening as described herein. The heat affected bead 902 is at the edge of the weld fusion zone 702 while the remainder of the work hardened weld assembly 900 extends from proximate the tube exterior surface 404 to proximate the tube interior surface 404. For instance, an interface segment of the weld interface 608 (not including the heat affected bead 902) extends from proximate the exterior surface 404 to proximate the interior surface 404 to provide enhanced characteristics to each of the weld interfaces 608 and thereby enhance the overall strength of the work hardened weld assembly 900. The heat affected bead 902 thereby constitutes an incidental decrease in mechanical characteristics relative to the base material while the remainder of the work hardened weld assembly 900, including the weld fusion zone 702 as well as the weld interface 608 extending from proximate the tube exterior surface 404 to proximate the interior surface 404, are all work hardened and accordingly have mechanical characteristics approaching (including equaling, near to, proximate or the like) those of the base material.
Figures 10A-F show another configuration of a component assembly 1000 including a work hardened weld assembly (or intermediate configurations of the assembly as the weld assembly is formed). As shown herein, the component assembly 1000 is plastically deformed during work hardening through deformation of both of the first and second components 1002, 1004, for instance, their component ends 1012 in addition to one or more features of the weld assembly including the weld filler, HAZ or the like.
Referring first to Figure 10A, the first and second components 1002, 1004 are shown in proximity with each of the component ends 1012 aligned with the other. As shown, the first and second components 1002, 1004 include at least some similar features to the previously described first and second components 302, 304 described herein. For instance, in this configuration, the first and second components 1002, 1004 are tubes and include tube exterior surfaces 1008 (e.g., an outer diameter, interior diameter or the like) and a tube interior surface 1010 (e.g., an inner diameter, interior diameter or the like). The component assembly 1000 is further shown with end profiles 1016 matching overall profiles 1014 of the remainder of the first and second components 1002, 1004. In one configuration, the overall profile 1014 is a consistent profile, for instance the shape, size, diameter or the like of the first and second components 1002, 1004 remains the same between ends of each of the components. At least portions of the end profiles 1016 in Figure 10A are similar to and provide a butt joint like the end profiles 512 show in Figure 5D. In the configurations shown in Figures 10A-F the end profiles 1016 further include portions of the components 1002, 1004 proximate to the ends, for instance the portion of the components deformed in Figures 10B, 10C or the like).
Figure 10B shows an intermediate configuration of the component assembly 1000. In this configuration, the component assembly 1000 includes the component ends 1012 having varied end profiles 1018 relative to the overall profile 1014 of the first and second components 1002, 1004. As shown in Figure 10B, the varied end profile 1018, includes a flared or enlarged profile relative to the overall profile 1014 (and the end profiles 1016 shown in Figure 10A). In other configurations, the varied end profile 1018 includes, but is not limited to, one or more of a shrunk end profile, a noncircular profile (relative to a base circular overall profile) or the like. In still other configurations, the varied end profile 1018 includes one or more of narrowing, corrugations or the like configured to provide a different shape to the end profile 1018 relative to the overall profile 1014. In still other configurations, the varied end profile 1018 is the initial configuration of the component ends 1012 of the first and second components 1002, 1004. In this configuration, the previous configuration shown, for instance, in Figure 10A of the component assembly 1000 is absent. Instead, the first and second components 1002, 1004 are provided in the varied profile shown herein, for instance, with the varied end profile 1018 relative to the overall profile 1014.
Figure 10C shows another intermediate configuration with a prepared weld joint 1020. In this configuration, the weld joint 1020 corresponding to a portion of the component ends 1012 is prepared for welding to connect the first and second components 1002, 1004 end-to-end. In this configuration, the weld interface 1022 of the weld joint 1020 includes one or more of the profiles described herein including, but not limited to, a U-shaped weld interface, a V-shaped weld interface, a J-shaped weld interface, a butt weld shaped weld interface 1022 (e.g., see Figures 5A-D), other weld interfaces including vertical or steep angled weld interfaces or the like (e.g., see Figure 4A). Optionally, the component ends 1012 forming the weld joint 1020 are prepared, for instance, by way of one or more of forming, machining or the like to provide the specified weld interfaces 1022.
Figure 10D shows the component assembly 1000 with the weld assembly 1024. A weld filler 1026 is provided in a corresponding weld recess formed by the weld interfaces 1022 previously described and shown, for instance, in Figure 10C. As shown, the weld filler 1026, projects from the first and second components 1002, 1004, for instance, form those portions of the tube exterior surfaces 1008 within the varied end profile 1018.
As further shown in Figure 10D, the weld assembly 1024 includes heat affected zones (HAZ) 1028 adjacent to the weld filler 1026. The HAZ 1028 is coincident with and included with the weld interfaces 1022. As previously described, the application of the heated weld filler 1026 to the weld interfaces 1022 anneals the base material of the first and second components 1002, 1004 along the weld interfaces 1022 (that is not otherwise melted and included in the fusion zone 1026). The annealing of the base material at the weld assembly 1024 creates a local weakness within the component assembly 1000 relative to the overall mechanical characteristics of the base material of the components 1002, 1004. For instance, as previously described, one or more of ultimate strength, yield strength, hardness, fatigue life or the like are decreased because of heating of the weld interfaces 1022 caused by the weld fusion zone 1026 to form the HAZ 1028.
The component assembly 1000 is shown again in Figure 10E. In this configuration, the weld fusion zone 1026 previously shown in Figure 10D is optionally shaped, for instance, by machining into the shaped weld fusion zone 1030. As shown, the shaped weld fusion zone 1030is substantially flush with the remainder of the component ends 1012 of the first and second components 1002, 1004. The component ends 1012 maintain the varied end profile 1018 relative to the overall profile 1014 of the components 1002, 1004. The shaping of the weld fusion zone 1030 shown in Figure 10E is optional. In other configurations, the weld fusion zone 1026 projecting from the weld assembly 1024 is maintained, for instance, to facilitate enhanced work hardening of one or more features of the weld assembly as described herein (e.g., with localized deformation of both the weld fusion zone 1026 and laterally extending and underlying weld interfaces).
Figure 10F shows the work hardened weld assembly 1032 including the component ends 1012 having a deformed end profile 1034 relative to the varied end profile 1018 previously shown in Figures 10D and 10E. In the configuration shown in Figure 10F, the deformed end profile 1034 matches the overall profile 1014. In other configurations, the deformed end profile 1034 does not match the overall profile 1014 but does otherwise vary relative to the varied end profile 1018 shown in Figure 10E. For instance, the deformed end profile 1034 is depressed relative to the overall profile 1014, enlarged relative to the overall profile 1014 and smaller than the original varied end profile 1018, includes a different shape or sized compared to the varied end profile 1018 or the like.
The plastic deformation of the component ends 1012 including the weld fusion zone 1026 and weld interfaces 1022 enhances the mechanical characteristics and correspondingly forms the work hardened weld assembly 1032. As previously described with regard to other configurations of a work hardened weld assembly, the work hardened weld assembly 1032 shown in Figure 10F includes enhanced mechanical characteristics relative to other weld assemblies described herein. In accordance with the present invention, the work hardened weld assembly 1032 includes one or more mechanical characteristics such as ultimate strength, yield strength, hardness, fatigue life or the like approaching the mechanical characteristics or matching the mechanical characteristics of the base material of the first and second components 1002, 1004.
In this configuration, the mechanical deformation of the component ends 1012 in contrast to the localized mechanical deformation of a weld assembly (e.g., shown in Figure 9) plastically deforms the entire region around the work hardened weld assembly 1032 as well as the weld assembly 1032 itself. Accordingly, while the weld fusion zone 1026 and the weld interfaces 1022 may in some configurations have a vertical or steep profile relative to the previously described weld assemblies provided herein, because the entirety of the component ends 1022 adjacent to the work hardened weld assembly 1032 are plastically deformed, the mechanical characteristics of the end profile including the weld assembly 1032 are improved. The work hardened weld assembly 1032 including the distributed work hardening shown in Figures 10A-F provides mechanical characteristics similar to those of the work hardened weld assembly 900 shown, for instance, in Figure 9.
Mechanical characteristics at the weld assembly 1032 are enhanced even with minimal preparation of the weld joint 1020 (e.g., a butt joint). For example, the weld joint 1020 instead of having the laterally extending weld interface 1022 shown (e.g., a U-shape, J-shape, V-shape or the like) is a substantially vertical or steep interface, such as a butt weld interface or deep U-shape weld interface. For instance, with a butt weld interface, the varied end profiles 1018 of the component ends 1012 are mated in a surface-to-surface manner, and in one example, a weld fusion zone 1026 is formed therebetween. By work hardening the entirety of the weld assembly including, for instance, the adjacent portions of the component ends 1012 having the varied end profiles 1018, the weld assembly including the weld fusion zone 1026 and weld interfaces 1022 having a flat (vertical) or steep configuration, are similarly work hardened to provide one or more mechanical characteristics proximate to the mechanical characteristics of the base material of the first and second components 1002, 1004.
In still other configurations, the work hardened weld assembly 1032 includes an autogenous weld. The autogenous weld assembly includes the material of the first and second components 1002, 1004 at the ends heated to fuse the components without a separate weld filler. In this configuration, because the end profile is deformed from the varied end profile 1018, for instance, to the deformed end profile 1034 or another profile different than the varied end profile 1018, the entirety of the weld assembly including the weld interfaces 1022 and the fused material of the first and second components are all work hardened. Accordingly, even annealed portions of the components 1002, 1004 used to provide an autogenous weld therebetween are consistently and reliably work hardened through plastic deformation of the end profiles 1018 to the deformed end profiles 1034 without the application and deformation of a weld filler.
Figure 11 shows a method 1100 for connecting at least first and second components, such as tubes. In describing the method 1100 reference is made to one or more components, features, functions or the like described herein. Where convenient reference is made to the components, features functions or the like with reference numerals. Reference numerals provided are exemplary and are not exclusive. For instance, the features, components, functions or the like described in the method 1100 include, but are not limited to, the corresponding numbered elements, other corresponding features described herein, both numbered and unnumbered as well as their equivalents.
At 1102, first and second components 302, 304, such as tubes are welded together. In one configuration, welding includes at 1104 filling a weld recess 602 bounded by weld interfaces 608, for instance along each of the ends of the first and second components. As shown in Figures 6, 7A-1, 7A-2 (as examples) the weld interfaces 608 extend from proximate an outer diameter toward an inner diameter of the components 302, 304. In one configuration, the weld interfaces form a weld bed and extend laterally from a bed root near a recess root 604 of the weld recess 602 to a bed opening (proximate one of the inner or outer diameter). The weld fusion zone 702 in the weld recess 602 is proximate to the localized heat affected zones 700 in each of the weld interfaces 608 (e.g., at 1106 in Figure 11). As described herein, the weld fusion zone 702 heats and anneals the weld interfaces 608 to form the HAZ.
At 1108, the method 1100 includes work hardening a weld assembly 710 (e.g., shown in Figures 7B or 8), for instance to the work hardened weld assembly 900 shown in Figure 9. As described herein, in one example the weld assemblies 710, 900 include the weld fusion zone 702 and the weld interfaces 608. In other configurations described herein the weld assemblies include an autogenous weld (e.g., the weld interfaces are heated and fused together). At 1110, the weld fusion zone 702 is deformed at least within the weld recess 602. As described herein, deformation of the weld fusion zone 702 includes deformation of a weld skirt 708 or 800 in other configurations. At 1112 each of the HAZ 700 are deformed according to deformation of the weld fusion zone 702. For instance, the weld fusion zone 702 is driven by plastic deformation into the weld interfaces 608 and thereby plastically deforms the weld interfaces 608 to minimize (e.g., decrease or eliminate) the HAZ 700.
Several options for the method 1100 follow. In one configuration, deforming each of the localized heat affected zones 700 includes deforming the weld fusion zone overlying the localized heat affected zones. In another configuration, the localized heat affected zones 700 are between the weld fusion zone 702 and a base material of the first and second components 302, 304 (see Figures 7B and 8). Deforming each of the localized heat affected zones 700 in this configuration includes deforming the weld fusion zone 702 toward the localized heat affected zones 700.
Optionally, work hardening the weld fusion zone 702 and the localized heat affected zones 700 includes supporting the base material of the first and second tubes 302, 304 along the inner diameter of the first and second tubes (e.g., with a mandrel, opposed inner work hardening tool or the like). In another configuration, work hardening the weld fusion zone 702 and the localized heat affected zones 700 of the weld interfaces 608 includes work hardening the weld fusion zone 702 and the localized heat affected zones 700 continuously from proximate a tube outer surface 404 (e.g., an outer diameter) to proximate a tube inner surface 402 (e.g., an inner diameter). In an additional configuration, work hardening the weld fusion zone 702 and the localized heat affected zones 700 of the weld interfaces 608 includes work hardening the weld fusion zone 702 and the localized heat affected zones 700 continuously from the outer diameter to the inner diameter.
The first and second component tubes 302, 304, in an example, include a base material having a specified strength (e.g., a yield strength of 620.53 MPa (90,000 psi) or more). In this example, work hardening the weld assembly 710 includes work hardening the weld assembly 710 to a work hardened strength proximate to the specified strength of the base material (e.g., a strength proximate to 620.53 MPa (90,000 psi)or within 68.95 MPa (10,000 psi) or less of the specified strength of the base material).
In other configurations, the method 1100 includes tapering the weld interfaces 608 at the respective ends of the first and second tubes 302, 304 from proximate the outer diameter to proximate the inner diameter, and the weld recess 602 includes a tapered weld recess corresponding to the tapered weld interfaces 608. The method 1100 optionally includes filling the tapered weld recess with a base weld portion (e.g., 704 and optionally 706) of the weld fusion zone 702, and covering the weld fusion zone 702 and portions of the first and second tubes 302, 304 proximate the outer diameter (e.g., tube outer surface 404) with a weld skirt 708, 800. In this example, deforming the weld fusion zone 702 within the weld recess 602 includes deforming the base weld portion (e.g., 704, 706) and the weld skirt 708 (or 800).
Optionally, the weld skirt 800 extends above the outside diameter (e.g., the tube outer surface 404) of the first and second tubes 302, 304 a specified height. Deforming the base weld portion and the weld skirt includes deforming the weld skirt 800 to a flush configuration relative to the outside diameter (e.g., the tube outer surface 404) from the specified height. Deforming the weld skirt 800 to the flush configuration from the specified height increases the strength of the weld assembly 900 including the weld fusion zone 702 and the weld interfaces 608 having the localized heat affected zones 700 to a work hardened strength proximate a specified strength of a base material of the first and second tubes. In one example, the weld skirt 708 shown in Figure 7B is shaped (e.g., machined or the like) into a planar configuration having the specified height.
In another example, the method 1100 includes changing an end profile 1016 of the respective ends of the first and second tubes 1002, 1004 relative to an overall profile 1014 of the tubes. For instance, the end profiles 1016 shown in Figure 10A are changed to a varied end profile having a different shape, size or the like relative to the overall profile 1014. In the examples shown in Figures 10B and 10C the varied end profile 1018 is enlarged relative to the overall profile 1014. In other examples, the end profile is decreased or provided with a different shape. Work hardening the weld assembly 1024 in this example includes deforming the end profile 1016 of the first and seconds tubes relative to the variable end profile (e.g., the profile 1018 shown in Figure 10C or other varied profiles). For instance, the variable end profile 1018 is deformed to have a profile matching the overall profile 1014. In another example, the variable end profile 1018 is deformed to have a profile different from each of the overall profile 1014 and the preceding variable end profile.
The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific configurations in which the disclosure can be practiced.
The scope of the present invention is defined in the appended claims.

Claims

A tube assembly (300; 1000) comprising:
at least a first tube (302; 1002) and a second tube (304; 1004) configured for coupling at respective ends (308; 1012), the first and second tubes each include:
a base material having a specified mechanical characteristic; and

a weld interface (422; 1022) at the respective end, the weld interface being proximate to an inner diameter (402; 1008) and an outer diameter (404; 1010) of the first

and second tubes; and

a work hardened weld assembly (310B; 1024) coupling the base material of each of the first and second tubes, the work hardened weld assembly includes:
a weld fusion zone (420; 1030) having a tapered configuration, which extends laterally from the inner diameter to the outer diameter of the first and second tubes, wherein the weld fusion zone, the weld interfaces and the base material of the first and second tubes form a stacked configuration;

weld interface segments (430), included in the weld interface, wherein the weld interface segments extend from proximate the inner diameter to proximate the outer diameter of the first and second tubes;

wherein the weld interface segments are sandwiched between the weld fusion zone and the base material of the respective first or second tubes as layers of the stacked configuration; and

wherein the weld fusion zone and the weld interface segments of the first and second tubes are work hardened, such that the weld interface segments of the first and second tubes and the weld fusion zone include mechanical characteristics approaching, namely equaling or near to the mechanical characteristics of the base material of the first and second tubes, wherein work hardening of the weld assembly is achieved through application of force transverse to the stacked configuration.
The tube assembly of claim 1, wherein the first and second tubes each include a heat affected bead (432) of the weld interface (422) spaced from the weld fusion zone (420).
The tube assembly of claim 1, wherein the specified mechanical characteristic of the base material includes a specified strength, and wherein the work hardened weld assembly, including at least the weld fusion zone and the weld interface segments, includes a work hardened strength proximate to the specified strength of the base material.
The tube assembly of claim 1, wherein the weld fusion zone includes:
a base weld portion (421) extending along the weld interfaces between the inner and outer diameters; and

a weld skirt (423) extending over portions of the first and second tubes proximate the weld interfaces, the weld skirt optionally extending over at least a portion of the weld interfaces proximate the outer diameter of the first and second tubes.
The tube assembly of claim 1, wherein the work hardened weld assembly includes a tapered weld recess (424) bounded by the weld interfaces, and the tapered weld recess tapers from a recess root (426) proximate the inner diameter of the first and second tubes to a recess opening (428) proximate the outer diameter of the first and second tubes, or from a recess root proximate the outer diameter of the first and second tubes to a recess opening proximate the inner diameter of the first and second tubes.
The tube assembly of claim 1, wherein the weld interface segments are included in a weld bed (608) extending laterally from proximate the inner diameter to proximate the outer diameter, the weld bed includes:
a weld bed ceiling extending along the weld fusion zone; and

a weld bed floor extending along the base material of the respective first and second tubes.
The tube assembly of claim 1, wherein the tube assembly includes welded and work hardened configurations:
in the welded configuration the first and second tubes proximate the respective ends have an end profile (1018) different relative to an overall profile (1014) of the first and second tubes (1002, 1004), and the weld fusion zone is between the weld interface segments; and

in the work hardened configuration the respective ends of the first and second tubes (1002, 1004) having the end profile (1018) are deformed relative to the welded configuration to match the overall profile (1014) of the first and second tubes, and each of the weld fusion zone, the weld interface segments and the first and second tubes proximate the weld interfaces are work hardened based on the deformation.
The tube assembly of claim 7, wherein the end profile in the welded configuration is larger compared to the overall profile (1014) of the first and second tubes (1002, 1004).
The tube assembly of claim 1, wherein the weld fusion zone includes one or more of an autogenous weld or a weld filler and resolidified base material.
The tube assembly of claim 1 comprising:
a graduated weld interface (608) at the respective end of each tube (302, 304); and wherein the work hardened weld assembly includes:
a weld bed floor (802) laterally extending from a bed root (604) to a bed opening (606), the weld bed includes the graduated weld interfaces of each of the first and second tubes extending from the bed root to the bed opening; and

the weld fusion zone coupled along the weld bed between the bed root and the bed opening, the weld fusion zone extending over the graduated weld interfaces;

wherein the weld fusion zone is work hardened from the bed opening toward the bed root and the graduated weld interfaces, and the weld bed, including the graduated weld interfaces of the first and second tubes, is work hardened between the weld fusion zone and the base material.
The tube assembly of claim 10, wherein the graduated weld interfaces are configured to be work hardened continuously from proximate an outer diameter to proximate an inner diameter of the first and second tubes.
The tube assembly of claim 10, wherein the specified mechanical characteristic of the base material includes a specified strength, and the work hardened weld assembly, including at least the weld fusion zone and the graduated weld interfaces, includes a work hardened strength proximate to the specified strength of the base material.
The tube assembly of claim 10, wherein the weld fusion zone overlies the graduated weld interfaces and the base material underlies the graduated weld interfaces; or includes one or more of an autogenous weld or a weld filler and resolidified base material.
The tube assembly of claim 10, wherein the weld bed, including the graduated weld interfaces, is sandwiched between the weld fusion zone and the base material.
An umbilical including the tube assembly of claim 10.
A method for coupling respective ends of first and second tubes, wherein the first and second tubes each include:
a base material having a specified mechanical characteristic; and

a weld interface (422; 1022) at the respective end, the weld interface being proximate to an inner diameter (402; 1008) and an outer diameter (404; 1010) of the first and second tubes (302, 304; 1002, 1004), wherein the method comprises:
tapering the weld interfaces at the respective ends of the first and second tubes from proximate the outer diameter to proximate the inner diameter,
welding the weld interface at the respective ends of each of the first and second tubes, wherein welding includes:
filling at least a weld recess bounded by the weld interfaces at respective ends of the first and second tubes with a weld fusion zone, wherein the weld recess includes a taper corresponding to tapering of the weld interfaces, and the weld fusion zone having a tapered configuration, which extends laterally from the inner diameter to the outer diameter of the first and second tubes,

wherein the weld fusion zone, the weld interfaces and the base material of the first and second tubes form a stacked configuration and weld interface segments are sandwiched between the weld fusion zone and the base material of the respective first and second tubes as layers of the stacked configuration, wherein the weld interface segments extend from proximate the inner diameter to proximate the outer diameter of the first and second tubes, wherein the weld fusion zone in the weld recess is proximate localized heat affected zones in each of the weld interfaces of the first and second tubes; and

work hardening the weld fusion zone and the weld interface segments of the first and second tubes such that the weld interface segments of the first and second tubes and the weld fusion zone include mechanical characteristics approaching, namely equaling or near to the mechanical characteristics of the base material of the first and second tubes, wherein work hardening involves an applied force acting transversely to the stacked configuration including the weld fusion zone, the localized heat affected zones of the weld interfaces and the weld interface segments, wherein work hardening the weld assembly includes:
deforming the weld fusion zone at least within the weld recess; and

deforming each of the localized heat affected zones with deformation of the weld fusion zone in at least the weld recess, wherein deforming each of the weld fusion zone and the localized heat affected zones is at the same time.
The method of claim 16, wherein deforming each of the localized heat affected zones includes deforming the weld fusion zone overlying the localized heat affected zones, or wherein the localized heat affected zones are between the weld fusion zone and a base material of the first and second tubes; and
deforming each of the localized heat affected zones includes deforming the weld fusion zone toward the localized heat affected zones.
The method of claim 16, wherein work hardening the weld fusion zone and the localized heat affected zones of the weld interfaces includes work hardening the weld fusion zone and the localized heat affected zones continuously from proximate the outer diameter to proximate the inner diameter or continuously from the outer diameter to the inner diameter.